The interview also links to this talk between Walter and Andrei Alexandrescu, of Modern C++ fame, who joined Walter to work on D (after working at Facebook for some time)) about a D project, warp (a C++ preprocessor), that Walter did for Facebook; the talk is about the D benefits Walter found while working on the project (such as the ease of changing the data structures to try different approaches, and how the ranges and the algorithms that operate upon them are somewhat decoupled).